The instant invention is in the field of circuit board manufacture, and particularly addresses the need that frequently crops up to remove a component that has already been soldered to the board. This sometimes occurs because after mounting the component it is found to be faulty.
Removal of components from a circuit board for replacement was simpler in past years due to the more simplified nature of the components. For example, most components from a few years ago had two parallel rows of leads which could be removed with an elongated blade by heating one side of the component and lifting it up, and then heating the other side and removing the component.
This simple procedure is clearly no longer possible when the lead row arrangement exceeds two parallel rows and enters the realm of polygonal arrangements, such as a square with a row of surface mount leads on each side of the square. Obviously, it is impossible to heat one side and then lift it up and then heat the others.
Because of the requirement that each and every one of the very fine leads must be heated to molten solder temperature simultaneously or the component will not release, past techniques and facilitating tools have created frustration. It is very common, using current techniques, to heat almost all of the surface mount leads adequately to release them from their pads, only to have one, or a small number, of the leads still bonded to their pads so that the entire component refuses to release. Of course, it is not apparent which leads are not releasing in most cases.
Because of the above-mentioned problem, repeated application of heat is often required to remove the component. This repeated heat may damage some types of circuit boards, or closely mounted components, or possible the component that is being removed.
There is a need for a simple, virtually full-proof removal means and method for removing state-of-the-art high density flat packs having quadrilateral lead row arrangements.